CVE-2021-2479Network attack vector

High-privilege remote denial of service

Published Oct 20, 2021 · Updated Sep 25, 2024

A denial-of-service vulnerability in MySQL Server 8.0.26 and earlier allows remote authenticated users to interrupt service via MySQL protocols. Oracle identifies the vulnerable locus only as Server DML and has not publicly described the malformed operation or specific code path. Exploitation requires a high-privilege account and network access; successful requests can hang the server or repeatedly crash it, causing complete service interruption without stated confidentiality or integrity impact.

CVSS severity4.9
Medium
EPSS probability2.65%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

A denial-of-service vulnerability in MySQL Server 8.0.26 and earlier allows remote authenticated users to interrupt service via MySQL protocols. Oracle identifies the vulnerable locus only as Server DML and has not publicly described the malformed operation or specific code path. Exploitation requires a high-privilege account and network access; successful requests can hang the server or repeatedly crash it, causing complete service interruption without stated confidentiality or integrity impact.

The record

CVE
CVE-2021-2479
Published
Oct 20, 2021
Updated
Sep 25, 2024
Vendor
Oracle Corporation
Product
MySQL Server
Classifications
T1499
Attack vector
network
Privileges
admin

Timeline

How it unfolded

  1. Oct 20, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 25, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=8.0.26 and prior

What conditions does exploitation require?

Attack vectornetwork
Required privilegesadmin

What is affected?

Oracle Corporation · MySQL Serverversion=8.0.26 and prior

Published CVSS scores

4.9Oracle CorporationCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesadmin
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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